Buckles for safety straps of this type are known but in different constructions. A buckle of the described type is published in German Gebrauchsmuster No. 1,974,922. This known construction relates to a belt buckle, in which the resiliently supported tongue is formed on a backwardly bent sheet metal part so that approximately in the center part of the housing a downwardly extending locking nose is constructed and forms the locking connection with the tongue which projects upwardly in the engaged condition. To effect a disengagement, a button which projects centrally above the housing is pressed down, which button holds down with bent webs the upright part of the tongue so that it can be pulled out of the housing and thus the connection of the two parts can be cancelled.
Such a buckle is difficult to use for safety straps because in safety straps for skis, the two buckle parts preferably must have a curved configuration, in order to better adjust to the boot surface or the foot of the skier. For this purpose, the arrangement of a relatively large push button with webs which are arranged spaced from one another at a considerable distance would therefore be disadvantageous. Also, the construction of the centrally arranged catch nose cannot be considered to be purposeful because only half the length of the tonque is used. Thus the entire buckle must have a relatively long length which is also disadvantageous in the case of safety straps. A movement of the push button toward the area of the housing, which area is in front in the opening direction, is not possible in the known solution because in this manner the front part of the tongue (also viewed in opening direction) could no longer be pressed down in a sufficient manner or -- which is also disadvantageous -- the material would have to be stressed too much, which would cause a premature wear of the buckle.
According to British Patent No. 818,988, the push button is mounted on a springy designed part of the housing, on which is provided an upwardly projecting catch nose which cooperates with a recess of the nonspringy tongue. In the inserted position of the tongue, the recess comes into engagement with the catch nose, which engagement can be cancelled by pressing down the push button so that the tongue can be pulled out of the housing. The push button can thereby be operated through an opening of the housing. To limit the path of operation of the push button, a web having bent portions is provided inside of the housing.
The housing consists of relatively many parts, so that the manufacture of the buckle requires much work and is expensive. In this structure, the design is a reversal of the first-discussed design in that here the springy part is mounted inside of the housing.
In a further known construction according to German Patent No. 271,782, the spring is also provided inside of the housing and the part to be introduced into the housing is formed as a button which is I-shaped in cross-section. The lower head plate of the button is loaded by the spring after engagement is brought about with the downwardly projecting projections of the housing. To cancel the lock, a pressure is exerted onto the upper head plate of the button which causes the lower head plate to press the spring down to cancel the engagement of the lower head plate with the projections and the closing part can be moved out of the housing.
A disadvantage of this known construction consists in the slightly complicated arrangement of the spring within the housing, furthermore in the stem of the button and the head plate having to be adjusted very exactly to the associated areas of the inside of the housing, to exclude fautly engaging conditions. If now, as already discussed above, in the case of a safety strap buckle the two parts require a curvature in addition, then a secure lock could be achieved only yet in a more complicated manner.
Finally in the case of a safety element according to German OS No. 2,217,378 (FIG. 11) a construction is known in which the tongue, which is introduced through an opening in the housing, can be brought into engagement with a catch hook pivotal about an axis which lies transversely with respect to the direction of introduction and engages with its nose a corresponding recess of the safety element. In this known construction, the spring hook is resilient.
A disadvantage of this construction lies in an additional catch hook and a pivot axis being needed aside from the housing and the tonque.
The object of the invention is to provide for a safety strap of the abovementioned type a buckle which does not have the mentioned disadvantages but wherein the security of the buckle is assured.
The purpose of the invention is attained by providing a housing, as is actually known, which has a resiliently supported part which, in the closed condition of the buckle, is loaded by an inserted, resiliently supported tongue.
Due to the fact that the resiliently supported tongue cooperates with a resiliently supported part of the housing, a secured lock is offered because the resiliently supported closing part has to adjust to a flexible part and thus practically the entire spring power is used to increase the depth of engagement or to maintain the closing position.
An advantageous form of the inventive buckle device lies in the resiliently supported part of the housing being formed in the housing lid. In this manner the housing is designed in a particularly simple way.
In order to design the buckle yet simpler, according to a further characteristic of the invention the button, the key or the like can be mounted on the resiliently supported part of the housing, preferably can be constructed in one piece with same.
A further thought of the invention lies in the fact that in the closed position of the buckle the tongue rests on the front inner edge of the housing viewed in opening direction. This construction has the advantage that the entire tongue length acts as a springy element and it is brought into the engagement position and carries out the largest path positioning movement between the pressed-down position and the engaging position.
A still further thought of the invention lies in the button, the key or the like being mounted on the area of the resiliently supported part of the housing, which lies above the free end of the resiliently supported tongue. This assures that the pressing down of the resiliently supported part of the housing occurs in an area which has to carry out the largest path to disengage the tongue.
An erroneously reversed or upside down insertion of the catch part is not possible. If this were not the case, the skier comes to expect a functional connection of the two parts of the buckle on the safety strap because during attaching of the safety strap, a practically unloaded condition exists and the springy action of the tongue is sufficient to falsely indicate the closing of the two parts. However, if a safety release occurs and a true load is created, then the buckle which is held together merely by friction opens up which causes not only the ski to be lost, but also an accident can be caused. This can take place particularly in those devices in which the housing is closed from below. The projection which exists in the case of an open bottom in the lower area of the housing can in turn lead to an unintended engagement between the tongue and the projection. A closing condition is created in this case, however, an opening of the buckle engaging the foot is very complicated.
This will be overcome according to a further characteristic of the invention by constructing inside of the housing a step which extends alongside of the housing, and by the body of the catch part having a step corresponding with said step, at least the sum of the heights of the two steps is larger than the free space between the opening of the housing and the height dimension of the area of the catch part which is to be introduced into the housing.
By using a step both in the housing and also on the catch part, it is assured that the catch part can only be introduced into the housing in the correct position, namely when the tongue lies in direction of the resiliently supported part of the housing. Since upon an intended introduction of a catch part in a position twisted at 180.degree. , namely upside down, both the step of the housing and also the catch part are active and it is sufficient if the sum of the two steps is larger than the clearance existing in elevational direction between catch part and housing opening.
The step could basically also exist in the lid part of the inlet opening of the housing and at the front end of the catch part. The longitudinal dimensions of these parts are, however, small, so that it is advantageous, to design the step construction as discussed above.